Doug Nelson did the welding so I have a little more confidence in it that if it was a Joe special, but I really don't like the way the thing feels, particularly in tight corners like the tower turn at FIR. I'm going to have Jim Fluckey take a look at it and either have it rebuilt or pull the lsd and put it in the one I bought from Doug. Unfortunately I won't get that done by this weekend so I'll have to run the welded diff. I was about 1.5 secs a lap slower with that tranny on Sunday over running my lsd on Saturday, but I hope I can improve that with a little practice.

To throw in some pennies here:

A tranny rebuild/refresh at a local porsche specialty shop with a mechanic who is arguably the best porsche mechanic I know runs $700 Labor + the parts you need. As I don't really price him due to his skill level I do not know if this is high or low but I do know he quotes book time. You can use this as a ball park for cost. His name is Mark at RSR motorsports and most of the PCA racers use him. I highly recommend him if you could guess hehehe

probbaly out of your way to get trans here though but just a thought

spec944#74 wrote:


Good idea,
Steve... Honeslty the welded diff is not the best option. I tend to believe it can be slight faster than open, but comes with increased risk of damage due to poor welds and due to the extra strain on the components mostly from turning in the side wheel in really tight turns.

Now a 1.5 sec increase in lap times is probably due to 2 things. 1) Your lack of familiarity with the diff. You will need to drive it different to take advantage of the 100% lock up all the time and to minimize its weaknesses. I have never driven with one so I can't say how, but it should add understeer everywhere. 2) you would need to adapt the set-up to accomodate this. Right now you have the car dialed in for an LSD so it is not perfect for the welded one.

So I believe if you worked on 1 and 2 you could gain back much of that 1.5 seconds. However in the end I feel it inferior to a good LSD anyway. So the best for you could be to keep the car as is and get the LSD back together and install it back in when you can.

Just so you know I have with and open diff because I never wanted weld my diff and suffer reliablity issues that could come with it.

One of the biggest issues with a locker is to complete your transition of braking, shifting and letting the clutch out before turn in. If you have not completed that, the car will try to step out if you have the least differential in engine speed and wheel speed. Trail braking is out as well.

Good luck and change it over as soon as you can.

Big Dog

Big Dog wrote:


Boy, you got that right Jim. I usually trail brake pretty deep into turn 1 at FIR and it got really squirrely on me, and like Joe said it understeered like crazy in the tight tower turn. I guess I'll try to dial in some oversteer to counteract that but with the way that thing wants to step out I'm not wild about that idea either. I am definitely going to do something different one way or the other. What I hope is that my lsd is still good and I can drop in in the new tranny. Doug said he has gone completely through the one he sold me and it is solid, so it would seem to be a good candidate for a transplant.

Gee steve I'm realy sorry about the transmission,,are you sure you didnt bust it when you left that donut on my car??